Five-year-old Malik still hides food beside his pillow before he goes to sleep - sometimes a piece of bread, sometimes fruit, sometimes a sweet.
His four-year-old sister Razan sets aside part of every meal, even when there is plenty on her plate.
Malik confuses the words "tent" and "home". Both children flinch at smoke and flashing red lights, bracing for bombs.
More than two years have passed since their parents got them out of Gaza. The memories have not left them.
On Monday, their father, Amjad Agha, and another Palestinian-Polish survivor, Ahmed Elsaftawy, walked into the district prosecutor's office in Wrocław, southern Poland, and filed a criminal complaint accusing senior Israeli officials of genocide, war crimes and crimes against humanity in the Gaza Strip.
